document.querySelectorAll('.s_button')[1].onclick =() => {
    let lists = document.querySelectorAll('.item');
    document.querySelector('#slide').appendChild(lists[0]);
}
document.querySelectorAll('.s_button')[0].onclick =() => {
    let lists = document.querySelectorAll('.item');
    document.querySelector('#slide').prepend(lists[lists.length - 1]);
}
function myFunction() {
    window.location.href='user.html';
}